Peer-to-peer mobile instant messaging method and device

ABSTRACT

A technique is provided for establishing peer-to-peer session-based instant messaging between mobile devices without the need for using an instant messaging registration or log-in server to provide presence information. Session-based instant messaging communications between mobile devices are established by embedding necessary address information in the telephony ringing signal between mobile devices.

CROSS REFERENCE TO RELATED APPLICATIONS

This application is a continuation-in-part of U.S. patent applicationSer. No. 10/817,994, filed Apr. 4, 2004.

FIELD OF THE INVENTION

The present invention relates generally to messaging techniques formobile devices, and more specifically, a technique to establishpeer-to-peer session-based instant messaging (“IM”) communications amongmobile devices without the need for IM registration.

BACKGROUND OF THE INVENTION

Current instant messaging (“IM”) technologies depend upon a registrationsystem to enable end users to communicate with one another. For example,to establish an IM session on AOL's Instant Messenger (“AIM”), eachparticipating end user must have registered with AOL and must log intoan AIM server in order to use the service. This registration systemcreates a virtual network of registered users and the value to a newuser in joining an IM service is directly related to the number ofexisting users already registered on the service. As more users registerto use an IM service, the value of the IM service to registered usersincreases since registered users will be able establish IM sessions withan increasing number of users. Known as a “network effect,” thisphenomenon causes a further tipping effect, which is the naturaltendency for few (or even a single) IM services to pull away from theircompetitors once they have gained an initial edge by registering acritical mass of users. This tipping effect tends to occur rapidly andstems, in part, from users' inclination to gravitate towards the IMservices that they expect will be become dominant. This tipping effectgives proprietary IM services such as AIM, Microsoft's NET MessengerService, and Yahoo! Messenger, that have achieved a large network ofregistered users, a strong barrier to entry into the IM market. As such,proprietary IM services may be reluctant to provide interoperability toother less established IM services since providing such access couldcannibalize their competitive network advantage.

From a technical perspective, the registration system used in IMservices is necessary to provide presence capabilities. In order toestablish an IM session, an end user must be registered with the IMservice so that the end user can log into the service's IM server, whichbroadcasts the end user's availability to engage in IM sessions to anauthorized group of the end users peers that have also registered andlogged into the IM server. The IM server also similarly provides the enduser with a list of registered peers that are available to engage in anIM session. When end users engage in IM sessions over a traditionalconnected network environment, presence capabilities are a criticalcharacteristic of an IM service because such capabilities are needed toprovide an end users peers with sufficient presence information (i.e.,IP address and port number) in order to locate the end user within thenetwork and establish a connection between the end user and a peer foran IM session. Furthermore, logging into an IM server also enables anend user to indicate whether or not he or she is physically present(e.g., sitting in front of a networked workstation or in front of alaptop that is connected the network) and willing to engage in an IMsession.

However, IM services for mobile devices, such as smartphones, appear tohave less a need for presence capabilities. Unlike establishing an IMsession on a laptop, desktop or workstation, where the end user mustbroadcast his or her availability and presence information on thenetwork when he or she is physically sifting in front of the laptop,desktop or workstation, establishing an IM session on a mobile devicedoes not suffer from the same presence issues because the end user ispresumed to be carrying the mobile device at all times. So long as themobile device has enough contact information (e.g., cellular telephonenumber, PIN number, etc.) to directly communicate with other mobiledevices through the underlying wireless network technology (e.g.,cellular technology, etc.), an IM session could be initiated andestablished in a manner similar to making and answering mobile phonecalls without the need for registering with or logging into an IM serverin order to broadcast presence information to other end users for IMpurposes.

Furthermore, unlike IM services in a traditional connected networkenvironment, successful end user adoption of an IM service betweenmobile devices would not suffer from reliance upon establishing acritical mass of end users through a registration system. In contrast,such an IM service would be instantly usable to any and all end users ofmobile devices so long as such mobile devices are already capable ofdirectly communicating with other mobile devices through the underlyingwireless mobile technology without needing further presence information(e.g., cellular phones directly communicating with other cellular phonesthrough cellular telephone numbers). As such, what is needed is a methodto establish IM sessions directly between mobile devices, where suchmobile devices are capable of directly communicating with other mobiledevices through the underlying wireless technology, such that no IMregistration or log-in server is needed to provide presence informationto other mobile devices for IM purposes.

SUMMARY OF THE INVENTION

The present invention provides a method for establishing a peer-to-peersession-based IM communications between mobile devices over a digitalmobile network system that supports data packet-based communications.Under the present invention, no IM registration or IM log-in server needbe used to provide presence information. Instead, a mobile deviceinitiating an IM session opens a listening port defined by an underlyingdata packet based network protocol. The initiating mobile device sendsan invitation message containing the network address, including thelistening port, of the initiating device to a target mobile devicethrough a page-mode messaging service supported by the digital mobilenetwork system. The initiating mobile device further utilizes andincorporates a unique identification number (e.g., telephone number, PINnumber, etc.) associated with the target mobile device into theinvitation message to locate and contact the target mobile device withinthe wireless mobile network. Alternatively, the invitation message maybe embedded in the telephony ringing signal sent to the target mobiledevice. Once the initiating mobile device receives a response from thetarget mobile device at the listening port, the two mobile devices areable to establish a reliable virtual connection through the underlyingdata packet-based network protocol in order to exchange text messagesdirectly between the two mobile devices through a session-basedcommunication.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 depicts a diagram of an environment for establishing an IMsession in accordance with the present invention between a first mobiledevice and a second mobile device in a GSM mobile network systemsupporting GPRS as a data packet-based communications service, SMS as atext messaging service, and TCP/IP as an underlying data packet basednetwork protocol.

FIG. 2 depicts a flow chart for a first embodiment for establishing apeer-to-peer session-based IM system in accordance with the presentinvention.

FIG. 3 depicts a flow chart for a second embodiment for establishing apeer-to-peer session-based IM system in accordance with the presentinvention.

DETAILED DESCRIPTION OF THE INVENTION

FIG. 1 depicts one environment to deploy an embodiment of the presentinvention. As depicted, the underlying digital mobile network system inthis environment is the Global System for Mobile communications (GSM)100 standard. Under the GSM standard, each of the mobile devices 105 and110 includes a Subscriber Information Module (SIM) card that containsunique identification information that enables the GSM system to locatethe mobile devices within the network and route data to them. A currentcommercial example of a mobile device (e.g., smartphone, PDA, handheld,etc.) that might be used in FIG. 1 could be Research In Motion's (RIM)BlackBerry handheld devices, which includes a QWERTY keyboard tofacilitate the typing of text. As depicted, a GSM architecture includesthe following components: base transceiver stations (BTS) 115 and basestation controllers (BSC) (120A or 120B) for managing the transmissionof radio signals between the MSC (defined below) and the mobile devices,mobile service-switching centers (MSC) (125A and 125B) for performingthe all switching functions and controlling calls to and from othertelephone and data systems, a home location register (HLR) 130 forcontaining all the administrative, routing and location information ofeach subscriber registered in the network, visitor location registers(VLR) (135A and 135B) for containing selected administrative informationabout subscribers registered in one HLR who are roaming in a anotherHLR, and an equipment identity register (EIR) (not shown) for containinga list of all valid mobile equipment on the network). As depicted inFIG. 1, in one architecture of a GSM network, there may be exist one HLRwhile there may exist multiple MSCs (each with a related VLR) which eachserves a different geographic area. The MSCs also provide the interfacefor the GSM network to more traditional voice networks 170 such as thePSTN. This underlying GSM architecture provides radio resourcesmanagement (e.g., access, paging and handover procedures, etc.),mobility management (e.g., location updating, authentication andsecurity, etc.), and communication management (e.g., call routing, etc.)in order to enable mobile devices in the GSM network to send and receivedata through a variety of services, including the Short Message Service(SMS), an asynchronous bi-directional text messaging service for shortalphanumeric messages (up to 160 bytes) that are transported from onemobile device to another mobile device in a store-and-forward fashion.

A GSM network within which the present invention may be deployed wouldalso support a page-mode messaging service, such as SMS, that reliesupon the underlying GSM mechanisms to resolve routing information inorder to locate destination mobile devices. Page-mode messaging servicessuch as SMS transmit messages that are independent or asynchronous witheach other, but there is no formal relationship between one message andanother. In contrast, an IM session that is implemented in accordancewith the present invention is a session-mode or session-based messagingservice where exchanged messages are formally associated in a sessionthereby minimizing the overhead costs of transmitting independentmessages. A GSM network supporting SMS text messaging may furtherinclude the following SMS specific components: a short message servicecenter (SMSC) (140A or 140B) for storing and forwarding messages to andfrom one mobile device to another, an SMS Gateway-MSC (SMS GMSC) forreceiving the short message from the SMSC (140A or 140B) andinterrogating the destination mobile device's HLR 130 for routinginformation to determine the current location of the destination deviceto deliver the short message to the appropriate MSC (125A or 125B). TheSMS GMSC is typically integrated with the SMSC 140. In a typicaltransmission of an SMS text message from an originating mobile device105 to a receiving mobile device 110, (i) the text message istransmitted from the mobile 105 to the MSC 125A, (ii) the MSC 125Ainterrogates its VLR 135A to verify that the message transfer does notviolate any supplementary services or restrictions, (iii) the MSC 125Asends the text message to the SMSC 140A, (iv) the SMSC 140A, through theSMS GMSC, interrogates the receiving mobile device's HLR 130 (byaccessing the SS7 network) to receive routing information for thereceiving mobile device 110, (v) the SMSC sends the text message to theMSC 125B servicing receiving mobile device 110, (vi) the MSC 125Bretrieves subscriber information from the VLR 135B, and (vii) the MSC125A transmits the text message to the receiving mobile device 110.Similar to other transactions on the GSM network, SMS text messagingutilizes telephone numbers as identifying addresses for mobile devicesand as such, utilizes the SS7 network signaling system through whichcellular service providers share information from the HLR with otherservice providers. As depicted in FIG. 1, SS7 based signalingcommunication is represented by the broken lines. In contrast, the solidlines in FIG. 1 represent data or voice based communications.

In addition to a page-mode messaging service such as SMS, a GSM networkwithin which the present invention may be deployed would also support adata packet based communications service, such as the General PacketRadio Service (GPRS), that enables TCP/IP transmission protocol basedcommunications between mobile devices within the network. As depicted inFIG. 1, a core GPRS network exists in parallel to the existing GSM corenetwork. The BSC 120 may direct voice traffic through the MSC (125A or125B) to the GSM network and data traffic through the Serving GPRSSupport Note (SGSN) (145A or 145B) to the GPRS network. Suchcommunication between the BSC (125A or 125B) and the SGSN (145A or 145B)may be, for example, based upon the IP network protocol communication155. As such, GPRS signaling and data traffic do not flow through thecore GSM network. Instead, the core GSM network is used by GPRS only fortable look-up in the HLR 130 and VLR (135A or 135B) to obtain routing,location and other subscriber information in order to handle usermobility. The SGSN (145A or 145B) serves as a “packet-switched MSC,”delivering data packets to mobile devices in its service area. TheGateway GPRS Support Note (GGSN) (150A or 150B) communicates with theSGSN (145A or 145B) through an IP based GPRS backbone 160 and serves asan interface to other external IP networks 165 such as the Internet andother mobile service providers' GPRS services.

When an IM service is offered in a traditional online packet basednetwork environment such as the Internet, the initiating computer musthave knowledge of the IP address (and possibly, a port) that has beenopened on the listening computer to receive IM communications. In orderto provide such IP address information, an IM service will set up alog-on or registration server through which end users can record the IPaddress on which they are currently listening for instant messagingcommunications. Because all end users have access to (i.e., know the IPaddress of) the registration server, they are able to obtain the IPaddresses of other end users who have also logged-on or registered onthe server and thereby initiate IM sessions directly with another endusers computer. Alternatively, the log-on or registration server mayserve as a forwarding agent between the two end users engaged in aninstant messaging session.

In contrast, in accordance with the present invention, a log-on orregistration server for IM or presence purposes can be eliminated on amobile network environment such as that depicted on FIG. 1. Through theuse of a page-mode messaging service, such as SMS, which transmitsmessages to mobile devices based upon their telephone numbers, aninitiating mobile device can transmit its IP address (and a listeningport) in an invitation message to a target mobile device through thetarget device's telephone number. Once the target device receives theinvitation message, it is able to contact the initiating mobile devicethrough the received IP address and the two devices can establish areliable virtual connection, such as a TCP connection, for session-basedIM communications. FIG. 2 depicts a flow chart depicting the steps takenby an initiating and target mobile device to establish an IM session inaccordance with the present invention. Initially, the initiating mobiledevice opens a TCP port to listen for communications from the targetmobile device 210. The target mobile device has also similarly opened anSMS listening port to receive invitation SMS text messages at thespecified SMS port 220. The initiating mobile device then transmits itsIP address (and TCP port) in an invitation SMS text message to thetelephone phone number and a specified SMS port of the target mobiledevice 230. The target mobile device receives the SMS text messagecontaining the initiating mobile device's IP address (and TCP port) atthe specified SMS port 240. The target mobile device extracts the IPaddress and TCP port from the SMS text message and opens its own TCPport 250. The target mobile device then transmits a request to establisha TCP connection to the initiating mobile device's IP address and TCPport 260. The initiating mobile device receives this request 270 and aTCP connection is established between the IP addresses and TCP ports ofthe initiating and listening mobile devices and these devices are ableto engage in an IM session over a reliable virtual connection 280.

Alternatively, FIG. 3 depicts a flow chart for an alternative embodimentdepicting steps to establish an IM session in accordance with thepresent invention. Initially, the initiating mobile device opens a TCPport to listen for communications from the target mobile device 310. Theinitiating mobile device, through its supporting telephone company, thenembeds its IP address (and TCP port) in the telephony ringing signalthat is transmitted to the target mobile device 320. For example andwithout limitation, the telephone company may use a frequency shiftkeyed (FSK) signal to embed the IP address (and TCP port) into thetelephony signal, similar to the traditional techniques used to embedother special service information, such as a caller ID, in thetraditional telephony context. The target mobile device receives thetelephony ringing signal from the initiating mobile device 330. Thetarget mobile device extracts the IP address and TCP port from thetelephone ringing signal and opens its own TCP port 340. The targetmobile device then transmits a request to establish a TCP connection tothe initiating mobile device's IP address and TCP port 350. Theinitiating mobile device receives this request 360 and a TCP connectionis established between the IP addresses and TCP ports of the initiatingand listening mobile devices and these devices are able to engage in anIM session over a reliable virtual connection 370.

While the foregoing detailed description has described the presentinvention using SMS, GSM, GPRS, and TCP/IP, other similar services andprotocols may be used in a variety of similar environments in which thepresent invention may be implemented. For example and withoutlimitation, rather than using SMS to transmit an IP address (and port)from the initiating mobile device to the listening mobile device throughthe devices' telephone numbers, an alternative embodiment of the presentinvention might use a PIN-to-PIN messaging technology (as, for example,offered in RIM's Blackberry handheld devices) to transmit the IP address(and port) through unique PIN numbers associated with the mobiledevices, or an alternative paging protocol using telephone numbers.Similarly, rather than using FSK to embed the IP address (and port) intothe telephony ringing signal, an alternative embodiment of the presentinvention might use a Duel Tone Multi-Frequency (DTMF) transmission toembed the IP address and port. Furthermore, the present inventioncontemplates that the actual protocol used during an established IMsession may also vary depending upon the preference of theimplementation. For example and without limitation, Message SessionRelay Protocol (MSRP) or any proprietary based protocol may be usedduring the IM session that is established in accordance with the presentinvention. Thus, various modifications, additions and substitutions andthe like can be made without departing from the spirit of the inventionand these are therefore considered to be within the scope of theinvention as defined in the following claims.

1. A method of establishing session-based instant messaging communications between mobile devices that support a data packet-based communications service over a digital mobile network system, the method comprising: opening a listening port on an initiating mobile device to receive communications through the data packet-based communications service; embedding an invitation message containing the address and the listening port of the initiating mobile device in a telephony ringing signal transmitted to a target mobile device. receiving a response from the target mobile device at the listening port on the initiating mobile device through the data packet-based communications service; and establishing a virtual connection through the data packet-based communications service for the session-based instant messaging session between the initiating mobile device and the target mobile device.
 2. The method of claim 1 wherein FSK is utilized to embed the address and the listening port of the initiating mobile device into the telephone ringing signal.
 3. The method of claim 1 wherein the data packet-based communications service is GPRS and the digital mobile network system is GSM.
 4. The method of claim 1 wherein the initiating mobile device and the target mobile device include QWERTY keyboards.
 5. The method of claim 1 wherein the address of the initiating mobile device is an IP address and the listening port is a TCP port.
 6. The method of claim 1 wherein the virtual reliable connection is a TCP connection.
 7. The method of claim 6 wherein instant messaging communications through the virtual connection utilizes MSRP.
 8. A mobile device enabled to establish session-based instant messaging communications with other mobile devices in a digital mobile network system, the mobile device comprising: programming means to support a data packet-based communications service over the digital mobile network system; programming means to extract an invitation message embedded in a telephony ringing signal initiated by the an initiating mobile device, the invitation message containing the address and a listening port of the initiating mobile device; programming means to send a response through the data packet-based communications service to the address and listening port of the initiating mobile device; and programming means to establish a virtual connection through the data packet-based communications service for session-based instant messaging communications between the mobile device and the initiating mobile device.
 9. The mobile device of claim 8 wherein the invitation message is embedded in the telephony ringing signal using FSK.
 10. The mobile device of claim 8 wherein the data packet-based communications service is GPRS and the digital mobile network system is GSM.
 11. The mobile device of claim 8 further comprising a QWERTY keyboard.
 12. The mobile device of claim 8 wherein the address of the initiating mobile device is an IP address and the listening port is TCP port.
 13. The mobile device of claim 8 wherein the virtual connection is a TCP connection.
 14. A computer program for establishing a session-based instant messaging communications between mobile devices that supports a data packet-based communications service over a digital mobile network system, the computer program comprising program code means for performing all the steps of claim 1 when the program is run on a computer.
 15. The computer program of claim 14 wherein FSK is utilized to embed the address and the listening port of the initiating mobile device into the telephony ringing signal.
 16. The computer program of claim 14 wherein the data packet-based communications service is GPRS and the digital mobile network system is GSM.
 17. The computer program of claim 14 wherein the initiating mobile device and the target mobile device include QWERTY keyboards.
 18. The computer program of claim 14 wherein the address of the initiating mobile device is an IP address and the listening port is a TCP port.
 19. The computer program of claim 14 wherein the virtual connection is a TCP connection.
 20. The computer program of claim 14 wherein the program code is distributed between the initiating mobile device and its supporting telephone company. 